K 10
svn:author
V 5
markj
K 8
svn:date
V 27
2016-10-17T07:23:07.242263Z
K 7
svn:log
V 518
Handle laundering run preemption properly.

Shortfall can preempt a background laundering, but not a shortfall
laundering. Therefore:
- make sure we don't reset the shortfall target if a shortfall request
  arrives while the system is already in shortfall, and
- make sure we acknowledge a shortfall request by resetting
  vm_laundry_request if it arrives during background laundering.

Also ensure that we sleep uninterruptibly between laundry cycles, and
rename "cycle" to make its use more clear.

Reviewed by:	alc

END